package com.lemontree.spring;

import org.springframework.beans.BeansException;
import org.springframework.beans.FatalBeanException;
import org.springframework.util.Assert;

import java.beans.PropertyDescriptor;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import java.util.Arrays;
import java.util.Collection;
import java.util.List;
import java.util.Map;
import java.util.Set;

/**
 * 扩展spring的BeanUtils，增加拷贝属性排除null值的功能(注：String为null不考虑)
 */
public class BeanUtils extends org.springframework.beans.BeanUtils {

    public static void copyPropertiesToMap(Object bean, Map<String, Object> map) throws Exception {
        copyPropertiesToMap(bean, map, "");
    }

    /**
     * @param bean
     * @param map
     * @param prefix key的前缀，如prefix="acc"，属性名为name，则key为acc.name
     * @throws Exception
     */
    public static void copyPropertiesToMap(Object bean, Map<String, Object> map, String prefix)
            throws Exception {
        if (bean == null)
            return;
        if (prefix != null && prefix.length() > 0) {
            prefix = prefix + ".";
        }
        for (Method m : bean.getClass().getDeclaredMethods()) {
            String mn = m.getName();
            if (mn.startsWith("get") && mn.length() > 3) {
                String property = mn.replaceFirst("get", "");
                property = property.substring(0, 1).toLowerCase() + property.substring(1);
                map.put(prefix + property, m.invoke(bean));
            }
        }
    }

    public static void copyNotNullProperties(Object source, Object target,
            String[] ignoreProperties) throws BeansException {
        copyNotNullProperties(source, target, null, ignoreProperties);
    }

    public static void copyNotNullProperties(Object source, Object target, Class<?> editable)
            throws BeansException {
        copyNotNullProperties(source, target, editable, null);
    }

    public static void copyNotNullProperties(Object source, Object target) throws BeansException {
        copyNotNullProperties(source, target, null, null);
    }

    @SuppressWarnings("rawtypes")
    private static void copyNotNullProperties(Object source, Object target, Class<?> editable,
            String[] ignoreProperties) throws BeansException {

        Assert.notNull(source, "Source must not be null");
        Assert.notNull(target, "Target must not be null");

        Class<?> actualEditable = target.getClass();
        if (editable != null) {
            if (!editable.isInstance(target)) {
                throw new IllegalArgumentException("Target class [" + target.getClass().getName()
                        + "] not assignable to Editable class [" + editable.getName() + "]");
            }
            actualEditable = editable;
        }
        PropertyDescriptor[] targetPds = getPropertyDescriptors(actualEditable);
        List<String> ignoreList = (ignoreProperties != null) ? Arrays.asList(ignoreProperties)
                : null;

        for (PropertyDescriptor targetPd : targetPds) {
            if (targetPd.getWriteMethod() != null
                    && (ignoreProperties == null || (!ignoreList.contains(targetPd.getName())))) {
                PropertyDescriptor sourcePd = getPropertyDescriptor(source.getClass(),
                        targetPd.getName());
                if (sourcePd != null && sourcePd.getReadMethod() != null) {
                    try {
                        Method readMethod = sourcePd.getReadMethod();
                        if (!Modifier.isPublic(readMethod.getDeclaringClass().getModifiers())) {
                            readMethod.setAccessible(true);
                        }
                        Object value = readMethod.invoke(source);
                        if (value != null || readMethod.getReturnType().getName()
                                .equals("java.lang.String")) {// 这里判断以下value是否为空，当然这里也能进行一些特殊要求的处理
                                                              // 例如绑定时格式转换等等，如果是String类型，则不需要验证是否为空
                            boolean isEmpty = false;
                            if (value instanceof Set) {
                                Set s = (Set) value;
                                if (s == null || s.isEmpty()) {
                                    isEmpty = true;
                                }
                            } else if (value instanceof Map) {
                                Map m = (Map) value;
                                if (m == null || m.isEmpty()) {
                                    isEmpty = true;
                                }
                            } else if (value instanceof List) {
                                List l = (List) value;
                                if (l == null || l.size() < 1) {
                                    isEmpty = true;
                                }
                            } else if (value instanceof Collection) {
                                Collection c = (Collection) value;
                                if (c == null || c.size() < 1) {
                                    isEmpty = true;
                                }
                            }
                            if (!isEmpty) {
                                Method writeMethod = targetPd.getWriteMethod();
                                if (!Modifier
                                        .isPublic(writeMethod.getDeclaringClass().getModifiers())) {
                                    writeMethod.setAccessible(true);
                                }
                                writeMethod.invoke(target, value);
                            }
                        }
                    } catch (Throwable ex) {
                        throw new FatalBeanException(
                                "Could not copy properties from source to target", ex);
                    }
                }
            }
        }
    }

}
